Apparatus for clearing liners



P 1940- L. P. BRANDEL 2,213,926

APPARATUS FOR CLEARING LINERS Filed July 22. 1938 Patented Sept. 3, 1940 APPABATUS FOR CLEARING LINERS Lewis P. Bramlel, Long Beach, Calif., assignor of one-third to William J. Flury and one-third to Frank Halien, both of Long Beach, Calif.

Application July 22, 1938, Serial No. 230,707

3 Claims.

This invention relates to an apparatus for cleaning out the perforations of well liners. As is well known, these liners are placed at the bottom of a well to hold back the formation.

I They consist; of a metal shell having perforationssometimes in the form of holes and sometimes in the form of slots extending longitudinally of the liner, and in some instances the slotsv extend horizontally around the liner. The perforations in these liners, in accordance withthe usual practice, are quite small, and on this account they frequently become clogged, and this greatly reduces the production .of the well. This is particularly true of wells in which the oil has a high specific gravity or increased amount of ingredients of an asphaltic nature.

The general object of this invention is to provide a simple apparatus for freeing the perforations of such a liner of obstructions, such as dirt Q or hardened material, that could clog up these perforations and prevent the passage of oil through them into the interior of the liner. In the practice ,of the method, a tool in the form of a disc is ,employed, and this tool'is pressed I against the inner. face of the liner and rolled along the same, thereby forcing the clogging ing the tool with parts in the relation which they have when the tool is in operation, as in cleaning out the linerperforations.

Figure 3 is a view illustrating some of the parts of the tool and showing them in the relation i which they have when in operation. In other words,this view illustrates parts of the tool, including three rollers or discs, and illustrates the manner in which they are related to each other while the tool is in operation. The relation of 10 these rollers or discs in Figure 3 is the same as that illustrated in Figure 2. 2

Figure 4 is a cross-section through the liner and indicates one of the working elements or rotary discs that are instrumental in the practice of the process. I Figure 5 ma cross-section taken about on the line 5-5 of Figure 1 andillustrating one of the discs in its retracted position; that is to say, the position that it has when the tool is passing down the well. 7

Figure 6 is a viewsimilar to Figure 5, but taken .on the line 6-6 of Figure 2 and illustrating one of the cleaning discs in operation.

material but of. the perforations. This requires considerableforce, and one of the objects of the invention is to provide a method, in the practice a of which the weight of the tool string is utilized in forcing the discs to, roll along the interior of the liner. Although the invention can be practised by employing a'single disc, it is preferable to employ a plurality of discs set to rotate in Before proceedingto a more detailed descrlption of the method and thetool which I prefer to employ, it should be stated that in practicing the invention, 1 support a disc or plurality of discs rotatably so that the disc or discs are supported in a substantially vertical plane within 80 the liner. With the disc or discs held in retracted position, the toolis lowered down the well to a point within the liner that is to have its a vertical planes, making an angle with each other and dividing the circumference into substantially I equal angles so that the. lateral thrust forces exerted by the. tool against the liner 'wall are substantially balanced.

u.Further objects of the hereinafter. p

A preferred embodiment of the invention is invention will appear described in the following specification, while the or rollers into different planes.

perforations cleared. The disc or discs are then forced in an outward direction so as to press their peripheries against the inner face of the liner, and while so held I move the'disc or discs along the inside of the liner. These discs preferably are formed with substantially radial spurs, and as the discs rotate, these spurs come 40 into contact with the rows of the perforations, thereby clearing them. In practising the method, it is necessary to repeat the operation many times. In doing this, after each act of rolling the discs albng the inside of the liner, they are retracted again from contact with the wall of the liner and the tool is then rotated through an angle so as to bring the wheels In this way, by repeating this operation again and again, substantially the entire perforated area can be sufficiently rolled to insure that the perforations will be substantially cleared of clogging material.

In practising the invention, I prefer to employ a tool, such as that illustrated in the drawing.

instance there are three pairs of these recessed cheeks to enable three rollers or discs 4 to be employed, and operating to hold the discs in three vertical planes making an angle of about 120 with each other. At these cheeks 3, slots are provided, said slots having lower extensions that are straight, that is to say, they extend in a direction parallel with the axis of the liner 8, but the upper portions of these slots have inclined extensions 1.. Between each opposite pair of recessed cheeks. 3 the mandrel l is provided with a transverse slot 8 that extends diametrically completely through the mandrel, and in each of these slots a rotary disc or roller 9 is mounted,

each roller being carried on a pin ID that operates as a shaft for it. The ends of these pins are received in the slots.

On each cheek 8 a slide II is provided, each slide having an enlarged head I 2 at its upper end and having a shank it that extends downwardly from the same. These slides are guided to slide longitudinally on the mandrel. Each head I2 is formed with a substantially triangular opening or eye i4 and these eyes receive the ends of the pins II). There are three of the slides II, each slide corresponding to one of the discs. When the tool is being lowered down the well, the heads l2 are located at the lower ends of the recessed cheeks 3, as indicated in Figure 1. The two upper slides II are substantially identical in construction, but

the lowest slide, which is indicated specifically bythe reference numeral 1 I, is formed with a cross-head l5 that connects its two shanks l3. These slides are mounted in such a way that the lower ends of the two upper slides abut against the heads of the slides just below them. The slot extensions 5 are located substantially centrally; that is to say, a line connecting two opposite slots at their lower ends would pass substantially along a diameter of the mandrel. Hence, when the shafts or pins H! are in the position indicated in Figure 1 the rollers or discs 9 are held in a substantially central position in the mandrel and in a retracted position. However, when the tool has arrived at the bottom of the well, by raising the tool it can be set in a position which will enable the downward movement of the mandrel to expand the tool as it were; that is to say, to move the discs out into an operative position, such as indicated in Figure 6. In order to enable this to be accomplished, the lower end of the mandrel is in the form of a shell I6 having a head I! at its lower end, and this head I! supports a stem I8 that is mounted to slide freely through a guide opening I9 in the head. On the lower end of the stem an enlarged head 20 is provided, and slidably mounted on this head there is provided a tube or barrel 2|, and this tube carries friction springs 22 which cooperate with the tube 2i to form a friction sleeve 23, the springs 22 of which engage the inner faoeof the liner wall.

Near the upper 'end of the tube 2| a latch 24 is provided, mounted on a pivot pin 25 and normally pressed inwardly against the side of the stem It by a small leaf spring 26. This latch 24 is mounted in a transverse slot 21 formed in the tube. The spring 26 may be carried on a cap 21 that is secured to the upper end of the tube 2|.

. In Figure 1 the tool is supposed to be in the act of passing down into the liner. As a matter of fact, at such a time the frictional resistance of the friction sleeve 28 will cause the cap 21 to lie against the lower face of the head I1. In other words the pressure of the head I! againstthe cap 21 will operate to push the sleeve 23 down through the liner. The upper end of the stem I8 is provided with a spider '28 that is of sufliciently large outside diameter to guide itself in the barrel or shell i 6. After the tool arrives at the proper point in the liner where the perforation clearing operation is to start, the tool string carrying the tool should be pulled upwardly; -When this occurs, the friction sleeve will remain in a fixed position temporarily by reason of its frictional contact with the liner, and the stem I! will be pulled upwardly by the rising mandrel. This will eventually bring the head 20 into the upper end of the tube 2| above the latch 24, whereupon the spring 28 will throw the latch down into a horizontal position, as indicated .in Figure 2. This latches the stem 18 in an elevated position above the latch and in such a way that when the mandrel i is lowered the spider 28 can come into contact with the cross-head I5 and therebycause a relative upward movement of the slides H. The first effect, however, is to push the slide ll up. As this occurs, its upper end strikes the lower ends of the shanks l3 of the intermediate roller or disc, and as this slide moves upwardly it will engage with the ends of the uppermost slides H. In this way, all of the slides will be pushed upwardly. This will cause the ends of the pins ill to ride into the upper ends of the inclined extensions 1 of the slots, thereby forcing the discs outwardly and causing their peripheries and their pointed teeth 29 to engage the wall of the liner. With the discs all held pressed outwardly in this way, the downward movement of the mandrel is continued and this causes the wheels to roll along on the interior of the liner. As this occurs, teeth 29 press themselves forcibly into the perforations 30 of the liner, thereby clearing them and in some cases pressing them outwardly so as to increase the size of the perforations.

This method is particularly advantageous where the perforations 30 are in the form of longitudinal slots in the liner.

After the downward rolling movement has extended throughout substantially the entire length of the liner, the tool string is then pulled up. This, of course, causes a relative downward movement of the stem i8 which is attached to the friction sleeve 23. This permits all of the slides to descend by gravity to their lowest positions on the mandrel, and in doing so they cause the pins 10 to ride into the lower extensions 5 of the slots. This retracts the rollers or discs, and while in this retracted position the tool string is given a slight rotation on its longitudinal axis, as indicated by the arrow in Figure 4. This would bring all of the discs or rollers into a new vertical plane slightly removed from the one in which they were located in theirfirst passage through the liner. The tool string is then permitted to descend, thereby causing the discs or rollers to move outwardly again into contact with the wall of the liner and the operation of rolling the inside of the liner is repeated. In this way, by repeatedly raising the tool string, rotating it and lowering itagain, the clearing operation is finally completed.

It is understood that the embodiment of the invention described herein is only one of the many embodiments this invention may take, and I do not wish to be limited in the practice of the invention, nor in the claims, to the particular embodiment set forth.

What I claim is:

'1. In a perforation cleaner for well liners, the combination of a mandrel having a plurality of slots extending through the same at different levels and in planes angularly displaced from each other, a disc carried in each slot and having circumferentially disposed teeth incapable of perforating the liner wall, said teeth operating to penetrate the perforations, a slide corresponding to each disc and guided to slide longitudinally on the mandrel, a pin carrying each disc, said man'- drel having pin slots to receive the ends of said pins, said pin slots having inclined extensions at their ends for pushing the discs outwardly-and into rolling contact with the liner, said mandrel having a bottom head, a stem guided through said bottom head, a friction sleeve carried bythe lower end of the stem to engage the tubing wall below or at the liner, said slides having heads at their upper ends with openings receivingthe ends of the pins, said friction sleeve operatingto efiect relative longitudinal movement of the slides and the mandrel and thereby moving the discs outwardly to contact the inner face of the liner.

2. In a perforation cleaner for well liners, the combination of a mandrel having a plurality of slots extending through the same at different levels and in planes angularly displaced from each other, a disc carried in each slot and having circumferentially disposed teeth incapable of perforating the liner wall, said teeth operating to penetrate the perforations, a slide corresponding to each disc and guided to slide longitudinally on the mandrel, said slides arranged so that when the bottom slide is pushed upwardly it will engage the next slide above the same and push said next slide upwardly against the uppermost slide, a pin carrying each disc, said mandrel having pin. slots to receive the ends of said pins, said pin slots having inclined extensions at their ends for pushing the discs outwardly through the agency of their contact with the ends of said pins, and causing the same to roll along the inner face of the liner, said mandrel having a bottom head, a .stem guided through said bottom head, a friction sleeve carried by the lower end of the when the mandrel is moved downwardly, thereby moving the discs outwardly to contact the inner face of the liner when the mandrel is moved downwardly at the liner.

3. In a perforation cleaner for well liners, the combination of a mandrel having a plurality of slots extending through the same at different levels and in planes angularly displaced from each other, a disc carried in each slot and having circumferentially disposed teeth incapable of perforating the liner wall, said teeth operating to penetrate the perforations, a slide corresponding to each disc and guided to slide longitudinally on the mandrel, said slides arranged so that when the bottom slide is pushed upwardly it will engage the next slide above the same and push said next slide upwardly against the uppermost slide, apin carrying each disc, said mandrel having pin slots. to receive the ends of said pins, said pin slots having inclined extensions at their ends for pushing the discs outwardly through the agency of their contact with the ends of ,said pins, and

causing the same to roll along the inner face of the liner, said mandrel having a bottom head,, a stem guided through said bottom head, said slides having heads at their upper ends with openings receiving the ends of the pins and permitting free lateral movement of the same, a friction sleeve carried by the lower end of the stem to engage the tubing wall below or adjacent the liner, said stem having means at its upper end for engaging the lowest of said, slides to force the'same and the upper slides in an upper direction to cause the discs to move outwardly through the agency of said pin slots, said sleeve constructed so that it is incapable during the movement of lowering the tool into the well, of imparting movement to said stem; and latch means associated with the sleeve for eifecting a connection between the sleeve and the stem by an upward movement after the tool has been lowered in the well to a poin opposite the liner to be cleaned.

LEWIS P. BRANDEL. 

